# Information Schema INNODB\_SYS\_INDEXES Table The [Information Schema](https://mariadb.com/docs/server/reference/system-tables/information-schema) `INNODB_SYS_INDEXES` table contains information about InnoDB indexes. The `PROCESS` [privilege](https://mariadb.com/docs/server/reference/sql-statements/account-management-sql-statements/grant) is required to view the table. It has the following columns: | Field | Type | Null | Default | Description | | ---------------- | ------------------- | ---- | ------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | INDEX\_ID | bigint(21) unsigned | NO | 0 | A unique index identifier. | | NAME | varchar(64) | NO | | Index name, lowercase for all user-created indexes, or uppercase for implicitly-created indexes; PRIMARY (primary key), GEN\_CLUST\_INDEX (index representing primary key where there isn't one), ID\_IND, FOR\_IND (validating foreign key constraint) , REF\_IND. | | TABLE\_ID | bigint(21) unsigned | NO | 0 | Table identifier, matching the value from [INNODB\_SYS\_TABLES.TABLE\_ID](https://mariadb.com/docs/server/reference/system-tables/information-schema/information-schema-tables/information-schema-innodb-tables/information-schema-innodb_sys_tables-table). | | TYPE | int(11) | NO | 0 | Numeric type identifier; one of 0 (secondary index), 1 (clustered index), 2 (unique index), 3 (primary index), 32 ([full-text index](https://mariadb.com/docs/server/ha-and-performance/optimization-and-tuning/optimization-and-indexes/full-text-indexes)). | | N\_FIELDS | int(11) | NO | 0 | Number of columns in the index. GEN\_CLUST\_INDEX's have a value of 0 as the index is not based on an actual column in the table. | | PAGE\_NO | int(11) | NO | 0 | Index B-tree's root page number. -1 (unused) for full-text indexes, as they are laid out over several auxiliary tables. | | SPACE | int(11) | NO | 0 | Tablespace identifier where the index resides. 0 represents the InnoDB system tablespace, while any other value represents a table created in file-per-table mode (see the [innodb\_file\_per\_table](https://mariadb.com/docs/server/server-usage/storage-engines/innodb/innodb-system-variables#innodb_file_per_table) system variable). Remains unchanged after a [TRUNCATE TABLE](https://mariadb.com/docs/server/reference/sql-statements/table-statements/truncate-table) statement, and not necessarily unique. | | MERGE\_THRESHOLD | int(11) | NO | 0 | | ## Example ```sql SELECT * FROM information_schema.INNODB_SYS_INDEXES LIMIT 3\G *************************** 1. row *************************** INDEX_ID: 11 NAME: ID_IND TABLE_ID: 11 TYPE: 3 N_FIELDS: 1 PAGE_NO: 302 SPACE: 0 MERGE_THRESHOLD: 50 *************************** 2. row *************************** INDEX_ID: 12 NAME: FOR_IND TABLE_ID: 11 TYPE: 0 N_FIELDS: 1 PAGE_NO: 303 SPACE: 0 MERGE_THRESHOLD: 50 *************************** 3. row *************************** INDEX_ID: 13 NAME: REF_IND TABLE_ID: 11 TYPE: 3 N_FIELDS: 1 PAGE_NO: 304 SPACE: 0 MERGE_THRESHOLD: 50 3 rows in set (0.00 sec) ``` *This page is licensed: CC BY-SA / Gnu FDL* {% @marketo/form formId="4316" %}